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EP-4740615-A1 - APPARATUS AND METHOD FOR MANAGING SESSION IN WIRELESS COMMUNICATION SYSTEM

EP4740615A1EP 4740615 A1EP4740615 A1EP 4740615A1EP-4740615-A1

Abstract

The present disclosure relates to a 5G communication system or a 6G communication system for supporting higher data rates beyond a 4G communication system such as long term evolution (LTE). According to an embodiment, a method performed by a UE is provided. The method comprises transmitting, to an access and mobility management function (AMF), information indicating that the UE supports network slice replacement feature, and in case that there is a protocol data unit (PDU) session associated with a single network slice selection assistance information (S-NSSAI) that needs to be replaced, receiving, from the AMF, a mapping of the S-NSSAI to an alternative S-NSSAI.

Inventors

  • LEE, HOYEON
  • SUH, DONGEUN

Assignees

  • Samsung Electronics Co., Ltd.

Dates

Publication Date
20260513
Application Date
20240716

Claims (15)

  1. A method performed by a user equipment (UE) in a wireless communication system, the method comprising: transmitting, to an access and mobility management function (AMF), information indicating that the UE supports network slice replacement feature; and in case that there is a protocol data unit (PDU) session associated with a single network slice selection assistance information (S-NSSAI) that needs to be replaced, receiving, from the AMF, a mapping of the S-NSSAI to an alternative S-NSSAI, wherein, in case that the S-NSSAI is replaced by the alternative S-NSSAI, the PDU session is associated with both of the S-NSSAI and the alternative S-NSSAI.
  2. The method of claim 1, further comprising, for an application, identifying, based on the S-NSSAI and not on the alternative S-NSSAI, whether to establish a PDU session for the application or to use the existing PDU session associated with the S-NSSAI for the application.
  3. The method of claim 2, wherein the identifying comprises: identifying whether the S-NSSAI matches with a first S-NSSAI associated with the application; and in case that the first S-NSSAI does not match with the S-NSSAI, identifying to establish a PDU session for the application.
  4. The method of claim 1, wherein a registration response message or a UE configuration update message includes the mapping which is transmitted to the UE.
  5. A user equipment (UE) in a wireless communication system, the UE comprising: a transceiver; and at least one processor configured to: transmit, to an access and mobility management function (AMF), information indicating that the UE supports network slice replacement feature; and in case that there is a protocol data unit (PDU) session associated with a single network slice selection assistance information (S-NSSAI) that needs to be replaced, receive, from the AMF, a mapping of the S-NSSAI to an alternative S-NSSAI, wherein, in case that the S-NSSAI is replaced by the alternative S-NSSAI, the PDU session is associated with both of the S-NSSAI and the alternative S-NSSAI.
  6. The UE of claim 5, wherein the at least one processor is further configured to: for an application, identifying, based on the S-NSSAI and not on the alternative S-NSSAI, whether to establish a PDU session for the application or to use the existing PDU session associated with the S-NSSAI for the application.
  7. The UE of claim 6, wherein the at least one processor is configured to: identify whether the S-NSSAI matches with a first S-NSSAI associated with the application; and in case that the first S-NSSAI does not match with the S-NSSAI, identify to establish a PDU session for the application.
  8. The UE of claim 5, wherein a registration response message or a UE configuration update message includes the mapping which is transmitted to the UE.
  9. A method performed by an access and mobility management function (AMF) in a wireless communication system, the method comprising: receiving, from a user equipment (UE), information indicating that the UE supports network slice replacement feature; in case that single network slice selection assistance information (S-NSSAI) becomes unavailable or congested, determining that the S-NSSAI is to be replaced with an alternative S-NSSAI; and in case that there is a protocol data unit (PDU) session associated with the S-NSSAI that needs to be replaced, transmitting, to the UE, a mapping of the S-NSSAI to the alternative S-NSSAI, wherein the mapping of the S-NSSAI to the alternative S-NSSAI is stored in UE context in the AMF.
  10. The method of claim 9, further comprising: identifying whether there is an established PDU session associated with the alternative S-NSSAI for the S-NSSAI being available again or not congested anymore; in case that there is the established PDU session associated with the alternative S-NSSAI for the S-NSSAI being available again or not congested anymore, identifying to cause the established PDU session to be transferred to the S-NSSAI; and transmitting, to a session management function (SMF), a PDU session update message to transfer the PDU session to the S-NSSAI.
  11. The method of claim 9, wherein the alternative S-NSSAI is determined based on at least one of information from a network slice selection function (NSSF), information from a policy control function (PCF), information from an operations, administration and maintenance (OAM), or local configuration.
  12. The method of claim 9, wherein a registration response message or a UE configuration update message includes the mapping which is transmitted to the UE.
  13. An access and mobility management function (AMF) in a wireless communication system, the AMF comprising: a transceiver; and at least one processor configured to: receive, from a user equipment (UE), information indicating that the UE supports network slice replacement feature; in case that single network slice selection assistance information (S-NSSAI) becomes unavailable or congested, determine that the S-NSSAI is to be replaced with an alternative S-NSSAI; and in case that there is a protocol data unit (PDU) session associated with the S-NSSAI that needs to be replaced, transmit, to the UE, a mapping of the S-NSSAI to the alternative S-NSSAI, wherein the mapping of the S-NSSAI to the alternative S-NSSAI is stored in UE context in the AMF.
  14. The AMF of claim 13, wherein the at least one processor is further configured to: identify whether there is an established PDU session associated with the alternative S-NSSAI for the S-NSSAI being available again or not congested anymore; in case that there is the established PDU session associated with the alternative S-NSSAI for the S-NSSAI being available again or not congested anymore, identify to cause the established PDU session to be transferred to the S-NSSAI; and transmit, to a session management function (SMF), a PDU session update message to transfer the PDU session to the S-NSSAI.
  15. The AMF of claim 13, wherein the alternative S-NSSAI is determined based on at least one of information from a network slice selection function (NSSF), information from a policy control function (PCF), information from an operations, administration and maintenance (OAM), or local configuration.

Description

APPARATUS AND METHOD FOR MANAGING SESSION IN WIRELESS COMMUNICATION SYSTEM The disclosure relates to an apparatus and method for managing a session in a wireless communication system. 5th generation (5G) mobile communication technologies define a wide frequency band for enabling a fast data rate and a new service, and can be implemented not only in a frequency band of a 'Sub 6 GHz' band, such as 3.5 GHz or the like but also implemented in an ultra-high frequency band (millimeter wave (mmWave)) of an 'Above 6 GHz' band, such as 28 GHz, 39 GHz, or the like. In addition, in a case of 6th generation (6G) mobile communication technologies that is referred to as Beyond-5G system, in order to achieve a data rate that is 50 times as fast as 5G mobile communication technologies and 1/10 the radio latency thereof, it has been considered to implement 6G mobile communication technologies in a terahertz band (for example, 95 GHz to 3 THz bands). In the early stage of the development of 5G mobile communication technologies, in order to support services and fulfill performance requirements in association with enhanced mobile broadband (eMBB), ultra reliable low latency communications (URLLC), and massive machine-type communications (mMTC), there has been ongoing standardization regarding beamforming and massive multiple input multiple output (MIMO) for decreasing path loss of radio waves and increasing transmission distances of radio waves in mmWave, supporting numerologies (for example, operating multiple subcarrier spacings) for efficiently utilizing mmWave resources and dynamic operation of slot formats, initial access technologies for supporting multi-beam transmission and broadbands, definition and operation of bandwidth part (BWP), new channel coding methods, such as a low density parity check (LDPC) code for large amount of data transmission and a polar code for highly reliable transmission of control information, layer 2 (L2) pre-processing, and network slicing for providing a dedicated network specialized to a specific service. Currently, there are ongoing discussions about improvement and performance enhancement of initial 5G mobile communication technologies in view of services to be supported by 5G mobile communication technologies, and there has been physical layer standardization about technologies, such as vehicle-to-everything (V2X) for aiding driving determination by autonomous vehicles based on information about positions and states of vehicles transmitted by the vehicles and for enhancing user convenience, new radio unlicensed (NR-U) aimed at system operations conforming to various regulation-associated requirements in unlicensed bands, new radio (NR) user equipment (UE) power saving, non-terrestrial network (NTN) which is UE-satellite direct communication for providing coverage in an area in which communication with terrestrial networks is unavailable, and positioning. Moreover, there has been ongoing standardization in air interface architecture/protocol regarding technologies, such as industrial Internet of things (IIoT) for supporting new services via interworking and convergence with other industries, integrated access and backhaul (IAB) for providing a node for network service area expansion by supporting a wireless backhaul link and an access link in an integrated manner, mobility enhancement including conditional handover and dual active protocol stack (DAPS) handover, and two-step random access for simplifying random access procedures (2-step random access channel (RACH) for NR). There also has been ongoing standardization in system architecture/service regarding a 5G baseline architecture (for example, service based architecture or service based interface) for combining network functions virtualization (NFV) and software-defined networking (SDN) technologies, and mobile edge computing (MEC) for receiving services based on UE positions. When such 5G mobile communication systems are commercialized, connected devices that have been exponentially increasing will be connected to communication networks, and it is accordingly expected that enhanced functions and performances of 5G mobile communication systems and integrated operations of connected devices will be necessary. To this end, new research is scheduled in connection with extended reality (XR) for efficiently supporting augmented reality (AR), virtual reality (VR), mixed reality (MR), or the like, 5G performance improvement and complexity reduction by utilizing artificial intelligence (AI) and machine learning (ML), AI service support, metaverse service support, drone communication, or the like. In addition, such development of 5G mobile communication systems will serve as a base for developing not only new waveforms for providing coverage in terahertz bands of 6G mobile communication technologies, multi-antenna transmission technologies, such as full dimensional MIMO (FD-MIMO), array antennas and large-scale antennas, metamaterial-based len